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Likely detection of pulsed high-energy γ-rays from millisecond pulsar PSR J0218+4232

Published online by Cambridge University Press:  12 April 2016

L. Kuiper
Affiliation:
SRON-Utrecht, Sorbonnelaan 2, 3584 CA, Utrecht, The Netherlands
W. Hermsen
Affiliation:
SRON-Utrecht, Sorbonnelaan 2, 3584 CA, Utrecht, The Netherlands
F. Verbunt
Affiliation:
Astronomical Institute Utrecht, 3508 TA, Utrecht, The Netherlands
A. Lyne
Affiliation:
University of Manchester, Jodrell Bank, Macclesfield SK11 9DL, UK
I. Stairs
Affiliation:
University of Manchester, Jodrell Bank, Macclesfield SK11 9DL, UK
D.J. Thompson
Affiliation:
Code 661, LHEA, NASA GSFC, Greenbelt, MD 20771, USA
G. Cusumano
Affiliation:
IFCAI CNR, Via U.La Malfa 153, I-90146, Palermo, Italy

Abstract

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We report on the likely detection of pulsed high-energy γ-rays from the binary millisecond pulsar PSR J0218+4232 in 100–1000 MeV data from CGRO EGRET. Imaging analysis demonstrates that the highly significant γ-ray source 2EG J0220+4228 (∼ 10σ) is for energies > 100 MeV positionally consistent with both PSR J0218+4232 and the BL Lac 3C66A. However, above 1 GeV 3C66A is the evident counterpart, whereas between 100 and 300 MeV PSR J0218+4232 is the most likely one. Timing analysis using one ephemeris valid for all EGRET observations yields in the 100-1000 MeV range a double-pulse profile at a ∼ 3.5σ significance level. The phase separation is similar to the component separation of ∼ 0.47 observed at X-rays. A comparison of the γ-ray profile with the 610 MHz radio profile in absolute phase shows that the two γ- ray pulses coincide with two of the three emission features in the complex radio profile.

Type
Part 5. High-Energy Observations
Copyright
Copyright © Astronomical Society of the Pacific 2000

References

Hartman, R.C., Bertsch, D.L., Bloom, S.D., et al. 1999, ApJS 123, 79 CrossRefGoogle Scholar
Kuiper, L., Hermsen, W., Verbunt, F., et al., 1998, A&A 336, 545 Google Scholar
Kuiper, L., Hermsen, W., Verbunt, F., et al., 2000, A&A, in preparationGoogle Scholar
Mineo, T., Cusumano, G., Kuiper, L., et al., 2000, A&A submittedGoogle Scholar
Navarro, J., de Bruyn, A.G., Frail, D.A., et al., 1995, ApJ 455, L55 Google Scholar
Stairs, I.H., Thorsett, S.E., Camilo, F., 1999, ApJS 123, 627 Google Scholar
Thompson, D.J., Bertsch, D.L., Dingus, B.L., et al., 1995, ApJS 101, 259 Google Scholar
Verbunt, F., Kuiper, L., Belloni, T., et al., 1996, A&A 311, L9 Google Scholar